Electric-oven heating unit.



F. KUHN F. E. SHAILOR.

ELECTRIC OVEN HEATING UNIT.

FILED MAY 8. 1915.

Eatented- J uly 18, 1916.

2 SHEETS-SHEET l.

F. KUHN I F. E. SHAILOR.

ELECTRiC OVEN HEATING UNIT.

APPLICATION FILED MAY a, 1915.

l ,l 9 l ,l 96. Patented 11115118, 1916.

2 SHEETS-SHEET Z.

|1 J 7 jg mi I O o i Y I iii. l w- @gw )www MMI-ww@ D, and having at its sides and inner edges.

A"inu'rED sTATEs PATENT OFFICE.

FRANK KUHN AND-FRANK E. SHAILOR, OF DETROIT, MICHIGAN,A ASSIGNORS T0 AMERICAN ELECTRICAL HEATER COMPANY, 0F DETROIT, MICHIGAN, A COB- I POBATION OVP-MICHIGAN.:

Enorme-OVEN `mia'rnm UNIT.

Specification of Letters latent. Patented J 1115r 18, 19216,

Application illed Iay 8, 1915. Serial No. 26,789.

' To all whom 1f-,may conom:

l Be it known that we, FRANK KUHN and FRANK E. SHAITQR, both citizens of the United States of America, residing at Detroit, inthe county of Wayne and State of heating of ovens, and it isv the`4object of the invention to obtain a 'construction of removable element vwhich'is thoroughly guarded against short circuiting, which uniformly distributes the heat and which f' possesses other advantages as hereinafter set forth.

lIn the drawings? Figure 1 is a perspective view of the elementj removed from the oven; Fig. 2 isa section through the oven with the element in positiontherein; Fig. 3 is a bottom plan view of a portion of the oven; and Fig. 4 isa sectionv in a vplane at right angles to that of Fig. 2.

l A lis an oven casing.

j B is our imprbVed unit, which is arranged above the bottom. of the oven ,and comprises a sheet metal pan or guard- C spaced from the oven bottom by supporting frames upturned .flanges E, with aI downturned flange F at its outer edge.

G are resistor coils which are woundnpon insulator .supports H, preferably porcelain tubes.

l I .is an insulator block'for the terminal contacts J, which contacts project rearward from the unit andare adapted toengage co-A operating contactsK in an insulator block L at the rear of the oven.

M are connectors between the contacts J and the resistor coils, which are preferably bentgto embrace the insulator Isupports H' insulator lsupports .H are secured at opposite ends to the frame D, and to prevent 'disf placement of'the resistor through the breaking of these tubes, a metallic strip O is vpassed completely through each tube, the

ends of' said Vstrip being secured to the end flanges D2 of the frame D. The up-V [per'p'art of the oven chamber is. heated by the convection of the hot air coming 1n direct contact with the resistor and the heated parts below the pan. -The air thus heated passes around the sides of the pan, andto pre'- vent short circuiting to the center, deflector plates P are placed upon the oven sides, and are adapted'to engage the upturned flanges E of the pan. Thus the hot air is. compelled to travel upward between the oven sides andthe deiectors P until it has reached the proper height within the oven chamber, when it passes over the tops of the delectors and toward the center of the oven space.

To lessen the cost of manufacture the pan with the parts of'I the frame D, as -well as the connectors M, clips N, etc., are' formed of sheet metal stampings and in assembling,

these parts are preferably secured as far aspossible by spot-welding.. There is also preferably acentral supporting post Qwhich .is .spot-welded to the bottom of the pan and supports the latter from theoven bottom.

. The insulatorblock I is secured by clips R also spot-welded to the bottom of the pan;

In use, the unit may be readily inserted or'withdrawn from the oven, the iianges E engaging the delector plates P forming guides for properly centering the pan and Adrawing the contacts J into engagement with the socket contacts K. *When in operation, thelleat generated in the resistor coils is communicated by radiation and convection to the bottom of the pan,l and by convection to thespace within the oven chamber, after first passing around the sides and over the deflectors P.y This willfsecure avery uniform 4distribution'of the heat, which may be varied as desired'by proper regulation' of the circuits which include the resistor coils. y y l What we claim as our invention isf- 1. The combination with an oven, of an electric heating unit therefor, comprising a resistor mounted'beneath said pan and in figged relation thereto and contacts for coupling said resistor in circuit when said pan is in place. v c

2. The combination with an oven, of an electrical heating unit therefor, comprising a pan forming a false bottom for said oven and removably engaging `the same, a depending frame on said pan forming a support therefor spaced from the oven bottom,`

an electrical resistor mounted in said depending frame, terminal contacts-for said resistor, an insulator support for said terminal contacts secured to the bottom of said pan, and coperating stationary contacts in said oven for engaging said terminal contacts when said pan is'in place.

3. The combination with an oven, of an velectrical heating unit therefor, comprising a pan forming a false bottom for the oven and having its edges spaced from the Walls thereof, a depending support for said pan, an electrical resistor mounted in said dependingxsupport, terminal contacts for said resistor having an insulator support on said 'from the sides and rear Wall thereof,fup

' turned flanges at the sides andrear of said pan, a downturned flange at'the front of said pan, a supporting frame for said pan to hold the same spaced from the oven bottom, an electrical resistor mounted` in saidl supporting frame, terminal contacts for said resistor having an insulator support on vthe bottom of said pan, coperating-contacts in said oven, and delector plates at the sides of the oven for engaging the upturned side flanges of' said pan to guilde thel same into proper position vand to register the contacts for engagement. l

5. The. combination with -an oven, of a g pan forming a false bottom for said oven,

having upturned side and rear flanges and a downturned front flange, frames upon opposite sides of the bottom of said pan provided With top delector platesspaced from said bottom of the pan and secured thereto,

'resistor coils mounted in said frames, terminal contacts having an insulator support on the bottom of said pan, and connectors between said contacts and resistor coils.

'i 6. The combination with an oven, of an electrical heating unit therefor, comprising a pan'having upturned side and rear flanges and a downturned front flange, a resistor mounted beneath said pan in fixed relatlon thereto and in the lspace between the same and thefoven bottom, terminal contacts for said resistor, cooperating contacts in said oven, and means for guiding said pan in engagement with said oven to space the sides and rear flanges thereof from the oven walls and to register said coperating contacts.

7. The combination with an oven, of an electric heatingunit therefor, comprising a pan forming a false bottom to the oven,

a resistor supported beneath said pan, and means for shielding said pan from direct radiation ofheat from said resistor, said means forming the support for the resistor.l

8. The combination with an oven, of an electrical heating unit therefor, comprising a pan forming a false bottom for said oven and removably,A engaging the same, a depending frame on said pan forming a support therefor spaced from the oven bottom, an electrical resistor mounted in said d epending frame, and means for shielding said pan fromdirect radiation of heat from said resistor.

,In testimony whereof We ailix our signa tures in presence of two Witnesses.

FRANK KUHN. p FRANK E. SHAILOR.

Witnesses: l

ROLAND DREssEL, 'ARCHIE E. PALMER. 

